Apparatus for removing the trimmed portions in a machine for cutting logs of paper and the like

Description

Field of the invention

[0001] The present invention generally relates to the field of paper converting machines and more precisely it relates to an apparatus for conveying the cut portions, such as rolls or stacks, and for removing the trimmed portions in a transversal cutting machine of logs of paper and the like.

Brief description of the prior art

[0002] In the production of rolls or stacks of sheets of paper and the like, for example absorbent for wipers or toilet paper, machines are known that work starting from large reels of a web having a large transversal width. From these machines logs of paper are delivered, having length equal to said transversal width of the web, and which are to be cut off into smaller portions, for example rolls of toilet paper, industrial wiping paper, stacks of napkins, etc.

[0003] The transversal cutting machines have just the object of cutting off into rolls or shorter stacks the logs of paper and comprise normally a bench with one or more slides onto which the logs to cut off are placed in turn. A stepped conveying system pushes a log portion beyond the cutting line of a rocking saw. At the cutting zone a clamping device holds the log upstream and downstream of the cutting line. Once cut off, the roll or the stack is carried away by a conveying apparatus provided downstream of the cutting zone.

[0004] The front and back ends of the log are then trimmed and the trimmed portions are taken away along an outlet conveyor.

[0005] The stepped movement of the log is carried out by means of pushers that protrude from a chain, which translates centrally in the slide on which the log lays.

[0006] A first problem of the existing machines is that the pushers have a limited surface and in particular are substantially rectangular strips. This shape is due to the limited clearance at the moment of the passage in the zone of conveying away the rolls or stacks. In fact, the removal is normally carried out by means of parallel belts close to one another, whereby the pushers, which are fastened to a loop chain, in the outlet zone have to pass between two belts and then turn back. The limited surface and the strip-like shape of the pushers have the consequence of a not regular cut of the logs end, in particular when the last roll or stack is cut off from the trimmed portion. In fact, since the trimmed portion is thin, the trimmed portion bends thus preventing the saw from cutting precisely.

[0007] A second problem of the existing machines is that the trimmed portions, at the beginning and end of the log, once cut, often lose their compact shape and become loose. In this way they disturb the outlet zone, where the belts cannot always convey them, and sometimes jam and block the passage of the rolls or stacks.

[0008] In order to avoid this drawback, in some types of rolls cutting-off machines pushing devices are provided that, after that sensors distinguish the trimmed portions from the rolls, push selectively the trimmed portions sideways. Alternatively, "traps" are provided, such as zones of fall of the trimmed portions obtained by distancing some belts so that they allow the passage of the rolls, which have larger size, causing only the trimmed portions to fall. In both these systems, the unevenness of the trimmed portions and their tendency to loosen cause the above-described problems.

[0009] Moreover, the presence of traps for the trimmed portions and the use of spaced belts to allow the passage of the pushers in the outlet zone have the drawbacks of creating points of possible jamming, with problems of stops of the production line and need of continuous control by the operators.

[0010] Finally, systems for conveying rolls are known with clamps or with sucking means that raise from the outlet zone only the rolls, but not the trimmed portions. These systems, however, are not much flexible in case of change of the height of cut and not suitable for all the types of products to cut off.

[0011] US4462287 describes an apparatus and a method according to the preamble of claims 1 and 3.

Summary of the invention

[0012] It is an object of the present invention to provide an apparatus for conveying and removing the trimmed portions from a transversal cutting machine in which the removal of the trimmed portions is easy, does not disturb the transport of the cut portions and does not allow the trimmed portions to follow the same path of the cut portions before being collected, overcoming the drawbacks of the prior art.

[0013] It is a further object of the present invention to provide an apparatus for conveying the cut portions of logs and for removing the trimmed portions thereof that, in case of log conveying means of the type comprising pushers, allows the use of pushers of large surface and that at the same time can easily pass through the outlet zone.

[0014] These objects are achieved by an apparatus having the features of claim 1 and by a method having the features of claim 3.

[0015] Advantageously, in case of pushing means of the logs through the cutting zone by means of pushers, the displacement of the outlet means allows the passage of the pushers also when they have large surface. In this case, the pushers comprise a large flat element, for example circular, whereby the logs are pushed by a larger surface thus allowing a cut of the trimmed portions with fewer defects.

Brief description of the drawings

[0016] Further characteristics and advantages of the apparatus according to the present invention will be made clearer with the following, but not limitative, exemplifying description of several exemplifying embodiments thereof, with reference to the attached drawings wherein:

• figure 1 shows a partial elevational side view of a transversal cutting machine comprising an apparatus according to the present invention for conveying rolls and removing trimmed portions;
• figure 2 shows a top plan view of the transversal cutting machine of figure 1;
• figure 3 shows a partial view from the back of the conveyance of the rolls by means of circular pushers.

Description of the preferred embodiments.

[0017] With reference to figures 1 and 2, an apparatus 1 for conveying rolls 2 and removing trimmed portions 3, according to the present invention, is arranged downstream of a transversal cutting machine 4.

[0018] The latter comprises a loading and supporting bench 5 of logs 6 to cut into rolls, a cutting zone 7 of the logs 6 by means of a rocking saw 8 and a gripping device 9.

[0019] Log 6 is pushed by a pusher 10 brought by a loop chain 11 and, just downstream of the cutting zone, a quick conveyor 12 is provided for carrying the rolls towards the apparatus 1 according to the invention.

[0020] Apparatus 1 comprises a first conveyor belt 15 and a second conveyor belt 16 fastened to a base 17.

[0021] More precisely, the first conveyor belt 15 is bound to the base 17 by means of a frame 18 pivotally connected about transversal hinges 19, whereby the conveyor belt 15, integrally to frame 18, can move away from the outlet zone by rotating to a position raised with respect to a transport plane 20 of log 6 and of rolls 2.

[0022] In such a raised position frame 18, shown in figure 1 with dotted line, is held by a cylinder 21, pivotally connected to base 17.

[0023] In use, the transversal cutting machine 4 produces a row of rolls 2 up to the end of log 6. At every cut saw 8 lowers and gripping device 9 clamps log 6. At the last cut, the last roll 2a is separated from a trimmed portion 3a brought by pusher 10. Therefore, saw 8 severs the last roll 2a from trimmed portion 3a by dropping onto the end of the log.

[0024] Then quick conveyor 12 carries last roll 2a away, while trimmed portion 3a is brought, as shown in figure 1, towards apparatus 1. As soon as last roll 2a has passed on the first conveyor belt 15, the latter is raised to the position shown with dotted line in figure 1, allowing at the same time the fall of trimmed portion 3a and the passage of pusher 10 that rotates about sprocket 22 following in succession the positions indicated with dotted lines.

[0025] At the same time, the transversal cutting machine has started to cut a second log 6, and after the first cut a second trimmed portion 3b is severed and carried by quick conveyor 12. A collector not shown receives trimmed portions 3a, 3b.

[0026] Then, before that the first cut portion of the following log 6 passes, just after the passage of the second trimmed portion 3b, the first conveyor 15 is lowered by cylinder 21.

[0027] According to the invention, therefore, the above mentioned advantages are achieved disturbing the least possible the rolls to carry away, collecting in a "clean and safe" way the trimmed portions and, allowing the use of a pusher 10 of size large enough to allow a regular separation of the first or last roll from the trimmed portions by means of saw 8.

[0028] The almost circular shape of pusher 10 is visible in figure 3 that covers almost all the cross section of log 6.

[0029] Notwithstanding reference has been made, in the description and in the drawings, to the cut of logs into rolls, it is clear that the same inventive concept can be applied to the cut of logs of different nature, for example logs of stacked sheets for the production of stacks of napkins, wipers, etc. In other embodiments which are not part of the invention the first conveyor belt 15 can also be moved away from the outlet zone in a different way than that shown, for example by rotating it about a hinge longitudinal with respect to the direction of transport of the rolls, or displacing it vertically or horizontally, respectively above or at the side of the outlet zone. These embodiments are not described in detail.

Claims

1. Apparatus for conveying cut portions starting from logs of paper material and the like, such as for the production of rolls (2,2a) or stacks, and for removing the trimmed portions (3a,3b) arranged on a transversal cutting machine, said machine comprising:

- a cutting zone (7,8) where said logs (6) are cut off into portions (2,2a);

- pushing means (10,11) of said logs (6) through said cutting zone;

- outlet means of the cut portions in an outlet zone downstream of said cutting zone; wherein in the outlet zone said outlet means comprise a first conveyor means (15) and a second conveyor means (16) fastened to a base (17), characterized in that said first conveyor means (15) is bound to the base (17) by means of a frame (18) pivotally connected about a hinge transversal (19) on a side directed towards said second conveyor means (16), whereby said first conveyor means (15) can displace from the outlet zone by rotating about said hinge (19) with respect to a direction of transport (20) of the cut portions (2), thus deviating the trimmed portions (3a, 3b) with respect to the cut portions (2,2a), whereby the trimmed portions do not reach said second conveyor (16) and can be collected.

2. Conveying apparatus according to claim 1, wherein said pushing means comprises pushers (10) having large surface, whereby the logs (6) are steadily pushed thus allowing the cut off of the trimmed portion (3a) from the last roll (2a) with larger support, said first conveyor means (15) moving away from said outlet zone also to allow the passage of said pushers (10) with large surface.

3. Method for conveying cut portions starting from logs of paper material and the like, such as for the production of rolls (2,2a) or stacks, and for removing the trimmed portions (3a, 3b) after a cutting phase, said cutting phase comprising the steps of:

- transport of said logs (6) through a cutting zone (7);

- cut off into portions (2,2a) of said logs;

- outlet of the cut portions (2,2a) and of the trimmed portions (3a, 3b) towards an outlet zone (1) downstream of said cutting zone (7);

- deviation of said trimmed portions (3a, 3b) with respect to said cut portions (2, 2a) at the end of said outlet step at the moment of the passage of said trimmed portions,

characterised in that said step of deviation comprises the step of rotation of a first conveyor means (15) with respect to a second conveyor means (16) on a side directed towards said second conveyor means, both conveyor means being provided for carrying away said cut portions, wherein said first conveyor (15) owing to said rotation, can displace from the outlet zone with respect to a direction of transport (20) of the cut portions (2), whereby the trimmed portions do not reach said second conveyor (16) and can be collected.

4. Method for conveying cut portions (2,2a) according to claim 8, wherein said step of transport of said logs is carried out by means of pushers (10) having large surface, said step of deviation of said trimmed portions with respect to said cut portions (2,2a) allowing also the passage of said pushers (10) having large surface without any interference with said conveyor means (15).

5. Method for conveying cut portions according to claim 9, wherein said step of deviation is carried out after the outlet of the last cut portion (2a) of each log, the displacement of said conveyor means causing

- fall of a first trimmed portion (3a) brought by one of said pushers (10) which can freely pass for turning back to push another log (6),

- fall of a second trimmed portion (3b) before that the first cut portion (2) of the following log (6) passes, just after the passage of the second trimmed portion (3b) the conveyor means (15) turning back to such a position that allows a regular transport of the following cut portions (2).

Ansprüche

1. Vorrichtung zum Befördern von geschnittenen Stücken, ausgehend von Papiermaterialklötzen und dergleichen, wie für die Herstellung von Rollen (2, 2a) oder Stapeln, und zum Entfernen der Abfallstücke (3a, 3b), die auf einer Querschneidmaschine angeordnet ist, wobei die Maschine Folgendes umfasst:

- eine Schneidzone (7, 8), in der die Klötze (6) in Stücke (2, 2a) geschnitten werden;

- Schiebemittel (10, 11), die die Klötze (6) durch die Schneidzone schieben;

- Auslassmittel für die abgeschnittenen Stücke in einer stromabwärts von der Schneidzone angeordneten Auslasszone, wobei die Auslassmittel in der Auslasszone ein erstes Fördermittel (15) und ein zweites Fördermittel (16), die an einer Basis (17) befestigt sind, umfassen, dadurch gekennzeichnet, dass das erste Fördermittel (15) mittels eines Rahmens (18) mit der Basis (17) verbunden ist, wobei der Rahmen auf einer zum zweiten Fördermittel (16) weisenden Seite um ein Querscharnier (19) schwenkbar verbunden ist, wobei das erste Fördermittel (15) sich von der Auslasszone weg bewegen kann, indem es sich in einer Transportrichtung (20) der abgeschnittenen Stücke (2) um das Scharnier (19) dreht und so die Abfallstücke (3a, 3b) von den abgeschnittenen Stücken (2, 2a) umlenkt, so dass die Abfallstücke den zweiten Förderer (16) nicht erreichen und gesammelt werden können.

2. Fördervorrichtung nach Anspruch 1, bei der das Schiebemittel großflächige Schieber (10) umfasst, durch die die Klötze (6) gleichmäßig geschoben werden, wodurch das Abschneiden des Abfallstücks (3a) von der letzten Rolle (2a) mit größerer Abstützung erfolgen kann, wobei das erste Fördermittel (15) sich von der Auslasszone weg bewegt, damit auch die großflächigen Schieber (10) passieren können.

3. Verfahren zum Befördern von geschnittenen Stücken, ausgehend von Papiermaterialklötzen und dergleichen, wie für die Herstellung von Rollen (2, 2a) oder Stapeln, und zum Entfernen der Abfallstücke (3a, 3b) nach einer Schneidphase, bei der man

- die Klötze (6) durch eine Schneidzone (7) transportiert;

- die Klötze in Stücke (2, 2a) schneidet;

- die abgeschnittenen Stücke (2, 2a) und die Abfallstücke (3a, 3b) zur Auslasszone (1) stromabwärts von der Schneidzone (7) abführt und

- die Abfallstücke (3a, 3b) am Ende des Abführschrittes, wenn die Abfallstücke passieren, von den abgeschnittenen Stücken (2, 2a) umlenkt,

dadurch gekennzeichnet, dass man beim Umlenken ein erstes Fördermittel (15) auf einer zum zweiten Fördermittel weisenden Seite bezüglich eines zweiten Fördermittels (16) dreht, wobei beide Fördermittel dazu vorgesehen sind, die abgeschnittenen Stücke wegzutragen, wobei sich der erste Förderer (15) aufgrund der Drehung bezüglich einer Transportrichtung (20) der abgeschnittenen Stücke (2) von der Auslasszone weg bewegen kann, so dass die Abfallstücke den zweiten Förderer (16) nicht erreichen und gesammelt werden können.

4. Verfahren zum Befördern von abgeschnittenen Stücken (2, 2a) nach Anspruch 8, bei dem das Transportieren der Klötze mittels großflächiger Schieber (10) durchgeführt wird, wobei durch das Umlenken der Abfallstücke bezüglich der abgeschnittenen Stücke (2, 2a) auch gestattet wird, dass die großflächigen Schieber (10) ohne Behinderung durch das Fördermittel (15) passieren können.

5. Verfahren zum Befördern von abgeschnittenen Stücken nach Anspruch 9, bei dem das Umlenken nach dem Abführen des letzten abgeschnittenen Stücks (2a) jedes Klotzes durchgeführt wird, wobei die Verschiebung des Fördermittels bewirkt,

- dass ein erstes Abfallstück (3a) fällt, das von einem der Schieber (10) herangebracht wird, der frei passieren und zum Schieben eines weiteren Klotzes (6) zurückkehren kann,

- dass ein zweites Abfallstück (3b) fällt, bevor das erste abgeschnittene Stück (2) des folgenden Klotzes (6) passiert,

wobei das Fördermittel (15) gleich nach dem Passieren des zweiten Abfallstücks (3b) in eine solche Position zurückkehrt, die einen regelmäßigen Transport der folgenden abgeschnittenen Stücke (2) gestattet.

Revendications

1. Appareil pour transporter des morceaux coupés à partir de bûches en matériau papier et analogue, tel que pour la production de rouleaux (2, 2a) ou de piles, et pour enlever les morceaux calibrés (3a, 3b) disposés sur une machine de coupe transversale, ladite machine comprenant :

- une zone de coupe (7, 8) où lesdites bûches (6) sont coupées en morceaux (2, 2a) ;

- un moyen de poussée (10, 11) desdites bûches (6) à travers ladite zone de coupe ;

- un moyen de sortie des morceaux coupés dans une zone de sortie en aval de ladite zone de coupe ; dans lequel dans la zone de sortie lesdits moyens de sortie comprennent un premier moyen de transport (15) et un second moyen de transport (16) fixé à une base (17), caractérisé en ce que ledit premier moyen de transport (15) est relié à la base (17) au moyen d'un cadre (18) rattaché de manière pivotante autour d'une charnière transversale (19) sur un côté orienté vers ledit second moyen de transport (16), de sorte que ledit premier moyen de transport (15) peut se déplacer à partir de la zone de sortie en tournant autour de ladite charnière (19) par rapport à un sens de transport (20) des morceaux coupés (2), déviant ainsi les morceaux calibrés (3a, 3b) par rapport aux morceaux coupés (2, 2a), afin que les morceaux calibrés n'atteignent pas ledit second transporteur (16) et peuvent être recueillis.

2. Appareil de transport selon la revendication 1, dans lequel ledit moyen de poussée comprend des poussoirs (10) ayant une grande surface, de sorte que les bûches (6) sont constamment poussées, permettant par conséquent la coupe du morceau calibré (3a) à partir du dernier rouleau (2a) avec un support plus grand, ledit premier moyen de transport (15) s'éloignant de ladite zone de sortie pour permettre également le passage desdits poussoirs (10) dotés d'une grande surface.

3. Procédé pour transporter des morceaux coupés à partir de bûches en matériau papier et analogue, tel que pour la production de rouleaux (2, 2a) ou de piles, et pour enlever les morceaux calibrés (3a, 3b) après une phase de coupe, ladite phase de coupe comprenant les étapes consistant à :

- transporter lesdites bûches (6) à travers une zone de coupe (7) ;

- couper en morceaux (2, 2a) lesdites bûches ;

- sortir les morceaux coupés (2, 2a) et les morceaux calibrés (3a, 3b) vers une zone de sortie (1) en aval de ladite zone de coupe (7) ;

- dévier lesdits morceaux calibrés (3a, 3b) par rapport auxdits morceaux coupés (2, 2a) à la fin de ladite étape de sortie au moment du passage desdits morceaux calibrés,

   caractérisé en ce que ladite étape de déviation comprend l'étape de rotation d'un premier moyen de transport (15) par rapport au second moyen de transport (16) sur un côté orienté vers ledit second moyen de transport, les deux moyens de transport étant prévus pour emporter lesdits morceaux coupés, dans lequel ledit premier transporteur (15), en raison de ladite rotation, peut se déplacer à partir de la zone de sortie par rapport à un sens de transport (20) des morceaux coupés (2), de sorte que les morceaux calibrés n'atteignent pas le second transporteur (16) et peuvent être recueillis.

4. Procédé pour le transport de morceaux coupés (2, 2a) selon la revendication 8, dans lequel ladite étape de transport desdites bûches est réalisée au moyen de poussoirs (10) ayant une grande surface, ladite étape de déviation desdits morceaux calibrés par rapport auxdits morceaux coupés (2, 2a) permettant également le passage desdits poussoirs (10) ayant une grande surface sans aucune interférence avec ledit moyen de transport (15).

5. Procédé pour le transport de morceaux coupés selon la revendication 9, dans lequel ladite étape de déviation est réalisée après la sortie du dernier morceau coupé (2a) de chaque bûche, le déplacement dudit moyen de transport provoquant

- la chute d'un premier morceau calibré (3a) apporté par un desdits poussoirs (10) qui peut passer librement afin de revenir en arrière et pousser une autre bûche (6),

- la chute d'un second morceau calibré (3b) avant que le premier morceau coupé (2) de la bûche suivante (6) passe, juste après le passage du second morceau calibré (3b), le moyen de transport (15) revenant à une position qui permet un transport constant des morceaux coupés suivants (2).

Drawing